Up to now, such a disc container casing has been proposed, in which an optical disc or a magnetic disc used as a recording medium for information signals is removably housed in the main casing member and in which the disc-shaped recording medium as it is contained in the casing main member can be loaded on the disc drive device.
As this type of the disc container casing, there is proposed such as casing disclosed in Japanese Laying-Open H-6-68641. The disc container casing, disclosed in this publication, includes a casing main member, having a disc housing section, and a cover member for closing the housing section. The disc housed in the housing section can be introduced or ejected by mounting the cover member for opening/closure with respect to the casing main member.
The disc container casing, disclosed in Japanese laying-Open H-6-68641, has a casing main member on left and right sides of which a pair of flexible cover retention members are unified with the casing main member. These cover retention members are engaged by a pair of retention pawls provided on the cover member for maintaining the closed state of the cover member, that is the state in which the disc housing section of the casing main member is closed by the cover member. By elastically shifting the cover retention members provided on left and right ends along the width and towards the inside of the casing main member, relative engagement of the cover retention member with engagement pawls provided on the cover member is released to enable opening of the disc housing section by the cover member.
Since the disc-shaped recording mediums housed in the casing main member can be exchanged as desired by openably mounting the cover member designed to cover the disc housing section, plural disc-shaped recording mediums can be selectively housed in one container casing for loading on the disc drive device. By providing the sole disc housing section, plural disc-shaped recording mediums can be selectively housed and loaded on the disc drive device, thus furnishing disc-shaped recording mediums at low costs.
Meanwhile, the information handled by an information processing apparatus, such as a computer, is increasing significantly in volume. The disc-shaped recording medium, such as an optical disc, used as a recording medium for information signals, is desired to be able to record a large quantity of the information. On the other hand, an optical disc having the picture information, such as a motion picture, is presented to the market extensively. Since the picture information supplied by a motion picture has an extremely large information volume, attempts are currently made towards increasing the recording capacity per disc for improving the recording density. In the disc-shaped recording medium increased in recording capacity to increase the recording density, attempts are made for narrowing the recoding track pitch or comminuting the signal area.
The disc-shaped recording medium, having a high recording density, is likely to be unable to record and/or reproduce information signals correctly due to deposition of the slightest amount of contaminants or grazing. Therefore, this type of the disc-shaped recording medium is desired to be housed in a disc container casing and to be loaded on the disc drive device as it is housed in the casing. If the disc-shaped recording medium can be loaded on or ejected from the disc drive device as it is housed in the disc container casing, the disc can be positively safeguarded against deposition of contaminants or grazing during handling such as loading or unloading for the disc drive device.
If the totality of the disc-shaped recording mediums are housed in the disc container casing members and offered in this state to the market, a large quantity of the disc container casings are required, such that the disc-shaped recording mediums cannot be furnished inexpensively. Moreover, if the totality of the disc-shaped recording mediums are housed in the disc container casing members, the storage space for the disc-shaped recording mediums is increased, such that the large quantity of disc-shaped recording mediums cannot be housed efficiently, while the circulation costs are also increased.
On the other hand, the disc container casing adapted to be loaded on a disc drive device as the disc-shaped recording medium is housed therein has an aperture to enable recording and/or reproduction for the disc-shaped recording medium housed in the disc housing section of the casing and a center opening via which is intruded a disc table of a disc rotation unit provided on the disc drive device for rotationally driving the disc-shaped recording medium housed in the disc housing section. The casing main member provided with the disc housing section carries a shutter member adapted for opening/closing the recording and/or reproducing aperture and the center opening. The casing main member includes a shutter supporting plate for supporting the distal end of the shutter member to enable the shutter member to be moved in stability along the surface of the casing main member.